12... g7g5  13. f4e5 A good practical choice. 13... e8g8 A new move and not in accordance with the position. This is clear evidence of Carlsen's bad form on the first day. 14. e5g3 Time to go back. After castling, Black's attack with h5 doesn't work so well, since the rook is poorly placed for such an endeavor. 14... h7h5 